1. Field of the Invention
The present invention relates generally to magnetic heads that are utilized with thin film hard disk data storage devices, and more particularly to the design and fabrication of a perpendicular magnetic head having a storage media heating element formed adjacent to a second magnetic pole tip of the write head components of the magnetic heads.
2. Description of the Prior Art
Hard disk drives generally include one or more rotatable data storage disks having a magnetic data storage layer formed thereon. Data in the form of small magnetized areas, termed magnetic data bits, is written onto the magnetic layers of the disks by a magnetic head that includes magnetic poles through which magnetic flux is caused to flow. Magnetic flux flowing from a pole tip portion of the magnetic poles in close proximity to the magnetic layer on the disk, causes the formation of the magnetic bits within the magnetic layer.
Generally, magnetic bits can be created where the magnetic field direction of each bit is either in the plane of the magnetic layer or perpendicular to the plane of the magnetic layer. Magnetic heads that form magnetic bits having in plane magnetic fields are termed longitudinal magnetic heads, whereas magnetic heads that form bits having a magnetic field that is perpendicular to the plane of the magnetic layer are termed perpendicular heads. The present invention relates particularly to perpendicular magnetic heads.
The continual quest for higher data recording densities of the magnetic media demands smaller bit cells, in which the volume of recording material (grains) in the cells is decreased and/or the coercivity (Hc) is increased. When the bit cell size is sufficiently reduced, the problem of the superparamagnetic limit will provide a physical limit of the magnetic recording areal density. Present methods to delay the onset of this limit in storage media include fabricating smaller magnetic grains that are decoupled from each other and which have very high coercivity. Additionally, write head technology methods include the use of higher magnetic moment materials, and using thermally assisted recording heads. The present invention relates to such thermally assisted recording heads in which a heating device is disposed within the magnetic head. Heat from the magnetic head temporarily reduces the localized coercivity of the media, such that the magnetic head is able to record data bits within the magnetic media. Once the disk returns to ambient temperature, the very high coercivity of the magnetic media provides the bit latency necessary for the recorded data disk.
In order to realize maximum advantage from perpendicular recording, there is a need for a write head that provides pole flux density near the saturation flux density of the head material, a pole thickness approximately equal to the trackwidth, a device to thermally heat the disk, and an efficient yoke design.